ARLP007 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 7  ARLP007
>From Tad Cook, K7RA
Seattle, WA  February 12, 2021
To all radio amateurs 

ARLP007 Propagation de K7RA

Sunspots are gone, with none seen since February 2 and 3. So there
were no sunspots from January 28 through February 1, then again none
after February 3. reported on Wednesday a small proto-sunspot
struggling to form, but by Thursday it was gone.

They also report 57% of the days so far in 2021 are spotless.  This
is the same as the percentage of spotless days in all of 2020.

Average daily solar flux was 72.8 over this reporting week, with
last week's average at 74.2. Average planetary A index increased
from 6.7 to 7.7, and average daily middle latitude A index rose from
4.6 to 6. These are still low, quiet numbers, quite favorable for
conditions on 80 and 160 meters, particularly during winter.

Predicted solar flux for the next 30 days is 75 on February 12-19,
78 on February 20-22, 76 on February 23-25, 74 on February 26, 73 on
February 27 through March 1, 72 on March 2-7, 74 on March 8-10, and
76 on March 11-13.

Flux values may rise to 78 again after the middle of March, just
before Spring Equinox in the Northern Hemisphere, which occurs on
March 20.

Predicted planetary A index is 5 on February 12-14, then 22 and 14
on February 15-16, 5 on February 17-20, then 20, 16 and 12 on
February 21-23, 5 on February 24-28, then 18 and 14 on March 1-2, 5
on March 3-4, then 8, 20 and 10 on March 5-7, and 5 on March 8-13.

Geomagnetic activity forecast for the period February 12 to March 9,
2021 from F.K. Janda, OK1HH.
"Geomagnetic field will be:
quiet on: February 12, 18-19, 25-27, March 5, 8-9.
quiet to unsettled on: February 13, 17, 24, March 3-4, 7.
quiet to active on: February 14-16, 20, 23, 28, March 6.
unsettled to active: February 21-22, March 1-2.
active to disturbed: none predicted.

"Solar wind will intensify on: February (15-17, 21-22,) 23-24,
(25-26,) March 2-4.
"-Parenthesis means lower probability of activity enhancement.
-Predictability of changes remains low, as there are very ambiguous

Thank you to Jon Jones, N0JK for this info on personal space weather
stations and a network tying them together:

Jon, who is in Eastern Kansas (EM28) also reported 6 meter
sporadic-E activity:

"Major 6 Meter Es opening across North America February 7-8 UTC. Es
first spotted around 1430 UTC and lasted until 0440 UTC.

"From Kansas had Texas in on Es around 1620 UTC.

"Later XE2ML (DL74) and XE2JS (DL78) at 2220 UTC.

"New Zealand was copied by stations in New England and W5LDA (EM15)
in Oklahoma was received by ZL1RS on 3 FT8 sequences."

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For more information concerning radio propagation, see and the ARRL Technical Information
Service web page at, For an
explanation of numbers used in this bulletin, see

An archive of past propagation bulletins is at More good
information and tutorials on propagation are at

Instructions for starting or ending email distribution of ARRL
bulletins are at .

Sunspot numbers for February 4 through 10, 2021 were 0, 0, 0, 0, 0,
0, and 0, with a mean of 0. 10.7 cm flux was 73.9, 72.8, 72.5, 73.2,
73.6, 70, and 73.7, with a mean of 72.8. Estimated planetary A
indices were 7, 6, 7, 21, 6, 4, and 3, with a mean of 7.7. Middle
latitude A index was 7, 3, 4, 18, 6, 3, and 1, with a mean of 6.
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